The present invention relates to a cover sheet assembling apparatus for an electronic component, and more particularly, it relates to an apparatus for inserting a cover sheet into an opening of a cover.
FIGS. 1 and 2 show a conventional four-element ladder-type filter. This filter comprises two series ceramic resonators 2 and 3, two parallel ceramic resonators 4 and 5, an input terminal plate 6, a ground terminal plate 7, an output terminal plate 8, an internal connection terminal plate 9 and a plate spring 10, which are stored in a box-type case 1. FIG. 3 is a circuit diagram showing the electrical connection thereof.
The input terminal plate 6 is provided on its one major surface with a protruding portion 6a which is in pressure contact with a central portion of the series resonator 2. The ground terminal plate 7 is provided on its both major surfaces with protruding portions 7a and 7b which are in pressure contact with central portions of the two parallel resonators 4 and 5 respectively. The output terminal plate 8 is provided on its both major surfaces with protruding portions 8a and 8b which are in pressure contact with central portions of the parallel resonator 5 and series resonator 3 respectively. The internal connection terminal plate 9 has a portion 9a which is inserted between the series resonator 2 and parallel resonator 4, a portion 9b which is arranged next to an outer major surface of the series resonator 3, and a coupling portion 9c which connects these portions 9a and 9b. Since the plate spring 10 is interposed between the portion 9b and an inner side surface of the case 1, the terminals 6-9 and the resonators 2-5 are in pressure contact with each other to be electrically connected.
A cover sheet 11 is inserted in an opening of the case 1, and a cavity which is defined by the cover sheet 11 and the opening is filled up with filler 12 such as resin, thereby the opening of the case 1 is sealed. Lead portions 6b, 7c and 8c of the input terminal 6, the ground terminal 7 and the output terminal 8 protrude from the opening of the case 1 so as to pass through the cover sheet 11.
When the ladder-type filter having the aforementioned structure is assembled in the conventional way, the cover sheet 11 is picked up by a forceps and manually inserted in the opening of the case 1. In particular, since the cover sheet 11 is previously provided with a plurality of slits for receiving the lead portions 6b, 7c and 8c of the terminals 6 to 8, it is necessary to scrupulously insert these lead portions in these slits so as to prevent the lead portions 6b, 7c and 8c from being bent. Thus, the conventional way for assembling the cover sheet 11 is required much time and much labor so that the assembling efficiency is lowered.